A sure sign of spring in Whatcom County is the appearance of a zippy little bird called the violet green swallow, whose in-flight acrobatics mimic a high-performance jet fighter.
“Their aerial skills are just phenomenal,” said Joe Meche, a birder and former president of the North Cascades Audubon Society. “Swallows most definitely, even more so than robins, are the true harbingers of spring.”
Violet green swallows are passerines, a term that describes their feet, which are designed for perching. Three toes point forward and one points backward. Violet green swallows are found only in western North America, according to the Cornell Lab of Ornithology.
They’re about 4 1/2 inches long with a wingspan of 10 1/2 inches, with short legs. They have green backs and heads, brown wings, a purple rump and white belly.
Arriving in Whatcom County in early to mid-April after a winter in Central America, they zip and dart through the air as they feast on flying insects. They often feed as a flock and can put on a dazzling midair display. They nest in a tree hole or rock cavity, using grass and twigs to build a small cup-shaped home. The female lays a clutch of four to six small white eggs.
“They spend very little time on the ground,” Meche said.
Meche is fascinated by violet green swallows that inhabit downtown Bellingham in the spring and summer, hunting for bugs. He builds cedar nesting boxes – which have a narrow diamond-shaped opening to deter predators – and once placed them around downtown to encourage the swallows to return.
Cornell Lab lists the bird as a species of least concern, although its numbers have declined by 25 percent over the past 50 years. Other organizations, such as Nestwatch.org, see it as a species in decline.